1
|
Ding Y, Tong J, Luo G, Sun R, Bei C, Feng Z, Meng L, Wang F, Zhou J, Chen Z, Li D, Fan Y, Song S, Wang D, Feng CG, Liu H, Chen Q, Yan B, Gao Q. Mycobacterial CpsA activates type I IFN signaling in macrophages via cGAS-mediated pathway. iScience 2024; 27:109807. [PMID: 38766355 PMCID: PMC11099328 DOI: 10.1016/j.isci.2024.109807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 02/08/2024] [Accepted: 04/22/2024] [Indexed: 05/22/2024] Open
Abstract
Type I interferon (IFN) production is crucial in tuberculosis pathogenesis, yet the bacterial factors initiating this process are incompletely understood. CpsA, protein of Mycobacterium marinum and Mycobacterium tuberculosis, plays a key role in maintaining bacterial virulence and inhibiting host cell LC3-associated phagocytosis. By utilizing CpsA full deletion mutant studies, we re-verified its essential role in infection-induced pathology and revealed its new role in type I IFN expression. CpsA deficiency hindered IFN production in infected macrophages in vitro as well as zebrafish and mice in vivo. This effect was linked to the cGAS-TBK1-IRF3 pathway, as evidenced by decreased TBK1 and IRF3 phosphorylation in CpsA-deficient bacterial strain-infected macrophages. Moreover, we further show that CpsA deficiency cause decreased cytosolic DNA levels, correlating with impaired phagosomal membrane rupture. Our findings reveal a new function of mycobacterial CpsA in type I IFN production and offer insight into the molecular mechanisms underlying mycobacterial infection pathology.
Collapse
Affiliation(s)
- Yue Ding
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Jingfeng Tong
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Geyang Luo
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Rongfeng Sun
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Cheng Bei
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Zhihua Feng
- Fujian Key Laboratory of Innate Immune Biology, Biomedical Research Center of South China, Fujian Normal University Qishan Campus, Fuzhou, China
| | - Lu Meng
- The Center for Microbes, Development and Health, Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences/University of Chinese Academy of Sciences, Shanghai, China
| | - Fei Wang
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Jing Zhou
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, College of Basic Medical Sciences; Institute of Infection and Inflammation, College of Basic Medical Sciences, China Three Gorges University, Yichang 443002, P.R China
| | - Zihan Chen
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, College of Basic Medical Sciences; Institute of Infection and Inflammation, College of Basic Medical Sciences, China Three Gorges University, Yichang 443002, P.R China
| | - Duoduo Li
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Yufeng Fan
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Shu Song
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Decheng Wang
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, College of Basic Medical Sciences; Institute of Infection and Inflammation, College of Basic Medical Sciences, China Three Gorges University, Yichang 443002, P.R China
| | - Carl G. Feng
- Immunology and Host Defence Laboratory, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW, Australia
| | - Haipeng Liu
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Qi Chen
- Fujian Key Laboratory of Innate Immune Biology, Biomedical Research Center of South China, Fujian Normal University Qishan Campus, Fuzhou, China
| | - Bo Yan
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Qian Gao
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| |
Collapse
|
2
|
Malet-Villemagne J, Yucheng L, Evanno L, Denis-Quanquin S, Hugonnet JE, Arthur M, Janoir C, Candela T. Polysaccharide II Surface Anchoring, the Achilles' Heel of Clostridioides difficile. Microbiol Spectr 2023; 11:e0422722. [PMID: 36815772 PMCID: PMC10100865 DOI: 10.1128/spectrum.04227-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 01/25/2023] [Indexed: 02/24/2023] Open
Abstract
Cell wall glycopolymers (CWPGs) in Gram-positive bacteria have been reported to be involved in several bacterial processes. These polymers, pillars for proteins and S-layer, are essential for the bacterial surface setup, could be essential for growth, and, in pathogens, participate most often in virulence. CWGPs are covalently anchored to peptidoglycan by proteins that belong to the LytR-CpsA-PSr (LCP) family. This anchoring, important for growth, was reported as essential for some bacteria such as Bacillus subtilis, but the reason why CWGP anchoring is essential remains unknown. We studied LcpA and LcpB of Clostridioides difficile and showed that they have a redundant activity. To delete both lcp genes, we set up the first conditional-lethal mutant method in C. difficile and showed that polysaccharide II (PSII) anchoring at the bacterial surface is essential for C. difficile survival. In the conditional-lethal mutant, C. difficile morphology was impaired, suggesting that peptidoglycan synthesis was affected. Because Lcp proteins are transferring CWPGs from the C55-undecaprenyl phosphate (also needed in the peptidoglycan synthesis process), we assumed that there was competition between PSII and peptidoglycan synthesis pathways. We confirmed that UDP-MurNAc-pentapeptide precursor was accumulated, showing that peptidoglycan synthesis was blocked. Our results provide an explanation for the essentiality of PSII anchoring in C. difficile and suggest that the essentiality of the anchoring of CWPGs in other bacteria can also be explained by the blocking of peptidoglycan synthesis. To conclude, our results suggest that Lcps are potential new targets to combat C. difficile infection. IMPORTANCE Cell wall glycopolymers (CWGPs) in Gram-positive bacteria have been reported to be involved in several bacterial processes. CWGP anchoring to peptidoglycan is important for growth and virulence. We set up the first conditional-lethal mutant method in Clostridioides difficile to study LcpA and LcpB involved in the anchoring of CWPGs to peptidoglycan. This study offers new tools to reveal the role of essential genes in C. difficile. LcpA and LcpB activity was shown to be essential, suggesting that they are potential new targets to combat C. difficile infection. In this study, we also showed that there is competition between the polysaccharide II synthesis pathway and peptidoglycan synthesis that probably exists in other Gram-positive bacteria. A better understanding of these mechanisms allows us to define the Lcp proteins as a therapeutic target for potential design of novel antibiotics against pathogenic Gram-positive bacteria.
Collapse
Affiliation(s)
| | - Liang Yucheng
- INSERM UMR-S 1138, Centre de Recherche des Cordeliers, Sorbonne Université, Université Paris Cité, Paris, France
| | - Laurent Evanno
- Biomolécules: Conception, Isolement et Synthèse (BioCIS), Université Paris-Saclay, CNRS, Orsay, France
| | | | - Jean-Emmanuel Hugonnet
- INSERM UMR-S 1138, Centre de Recherche des Cordeliers, Sorbonne Université, Université Paris Cité, Paris, France
| | - Michel Arthur
- INSERM UMR-S 1138, Centre de Recherche des Cordeliers, Sorbonne Université, Université Paris Cité, Paris, France
| | - Claire Janoir
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, Jouy-en-Josas, France
| | - Thomas Candela
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, Jouy-en-Josas, France
| |
Collapse
|
3
|
Cerezo-Cortés MI, Rodríguez-Castillo JG, Mata-Espinosa DA, Bini EI, Barrios-Payan J, Zatarain-Barrón ZL, Anzola JM, Cornejo-Granados F, Ochoa-Leyva A, Del Portillo P, Murcia MI, Hernández-Pando R. Close Related Drug-Resistance Beijing Isolates of Mycobacterium tuberculosis Reveal a Different Transcriptomic Signature in a Murine Disease Progression Model. Int J Mol Sci 2022; 23:ijms23095157. [PMID: 35563545 PMCID: PMC9100210 DOI: 10.3390/ijms23095157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Revised: 04/22/2022] [Accepted: 04/22/2022] [Indexed: 12/10/2022] Open
Abstract
Mycobacterium tuberculosis (MTB) lineage 2/Beijing is associated with high virulence and drug resistance worldwide. In Colombia, the Beijing genotype has circulated since 1997, predominantly on the pacific coast, with the Beijing-Like SIT-190 being more prevalent. This genotype conforms to a drug-resistant cluster and shows a fatal outcome in patients. To better understand virulence determinants, we performed a transcriptomic analysis with a Beijing-Like SIT-190 isolate (BL-323), and Beijing-Classic SIT-1 isolate (BC-391) in progressive tuberculosis (TB) murine model. Bacterial RNA was extracted from mice lungs on days 3, 14, 28, and 60. On average, 0.6% of the total reads mapped against MTB genomes and of those, 90% against coding genes. The strains were independently associated as determined by hierarchical cluster and multidimensional scaling analysis. Gene ontology showed that in strain BL-323 enriched functions were related to host immune response and hypoxia, while proteolysis and protein folding were enriched in the BC-391 strain. Altogether, our results suggested a differential bacterial transcriptional program when evaluating these two closely related strains. The data presented here could potentially impact the control of this emerging, highly virulent, and drug-resistant genotype.
Collapse
Affiliation(s)
- María Irene Cerezo-Cortés
- Laboratorio de Micobacterias, Departamento de Microbiología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá 111321, Colombia; (M.I.C.-C.); (J.G.R.-C.)
| | - Juan Germán Rodríguez-Castillo
- Laboratorio de Micobacterias, Departamento de Microbiología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá 111321, Colombia; (M.I.C.-C.); (J.G.R.-C.)
| | - Dulce Adriana Mata-Espinosa
- Sección de Patología Experimental, Departamento de Patología, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México 14080, Mexico; (D.A.M.-E.); (E.I.B.); (J.B.-P.); (Z.L.Z.-B.)
| | - Estela Isabel Bini
- Sección de Patología Experimental, Departamento de Patología, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México 14080, Mexico; (D.A.M.-E.); (E.I.B.); (J.B.-P.); (Z.L.Z.-B.)
| | - Jorge Barrios-Payan
- Sección de Patología Experimental, Departamento de Patología, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México 14080, Mexico; (D.A.M.-E.); (E.I.B.); (J.B.-P.); (Z.L.Z.-B.)
| | - Zyanya Lucia Zatarain-Barrón
- Sección de Patología Experimental, Departamento de Patología, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México 14080, Mexico; (D.A.M.-E.); (E.I.B.); (J.B.-P.); (Z.L.Z.-B.)
| | - Juan Manuel Anzola
- Grupo de Biotecnología Molecular, Grupo de Bioinformática y Biología Computacional, Corporación CorpoGen, Bogotá 110311, Colombia; (J.M.A.); (P.D.P.)
- Universidad Central, Facultad de Ingeniería y Ciencias Básicas Bogotá, Bogotá 100270, Colombia
| | - Fernanda Cornejo-Granados
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca 62210, Mexico; (F.C.-G.); (A.O.-L.)
| | - Adrian Ochoa-Leyva
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca 62210, Mexico; (F.C.-G.); (A.O.-L.)
| | - Patricia Del Portillo
- Grupo de Biotecnología Molecular, Grupo de Bioinformática y Biología Computacional, Corporación CorpoGen, Bogotá 110311, Colombia; (J.M.A.); (P.D.P.)
| | - Martha Isabel Murcia
- Laboratorio de Micobacterias, Departamento de Microbiología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá 111321, Colombia; (M.I.C.-C.); (J.G.R.-C.)
- Correspondence: (M.I.M.); (R.H.-P.)
| | - Rogelio Hernández-Pando
- Sección de Patología Experimental, Departamento de Patología, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Ciudad de México 14080, Mexico; (D.A.M.-E.); (E.I.B.); (J.B.-P.); (Z.L.Z.-B.)
- Correspondence: (M.I.M.); (R.H.-P.)
| |
Collapse
|
4
|
Genetic factors related to the widespread dissemination of ST11 extensively drug-resistant carbapenemase-producing Klebsiella pneumoniae strains within hospital. Chin Med J (Engl) 2021; 133:2573-2585. [PMID: 32969865 PMCID: PMC7722564 DOI: 10.1097/cm9.0000000000001101] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Background Carbapenemase-producing Klebsiella pneumoniae (CP-Kp) poses distinct clinical challenges due to extensively drug resistant (XDR) phenotype, and sequence type (ST) 11 is the most dominant blaKPC-2-bearing CP-Kp clone in China. The purpose of this current retrospective study was to explore the genetic factors associated with the success of XDR CP-Kp ST11 strains circulated in the intensive care unit (ICU) of a Chinese tertiary hospital. Methods Six ST11 XDR CP-Kp strains were identified between May and December 2014 and validated by minimum inhibitory concentration examination, polymerase chain reaction, and pyrosequencing. The six ST11 XDR CP-Kp, as well as three multi-drug resistant (MDR) and four susceptible strains, were sequenced using single-molecule real-time method. Comprehensively structural and functional analysis based on comparative genomics was performed to identify genomic characteristics of the XDR ST11 CP-Kp strains. Results We found that ST11 XDR blaKPC-2-bearing CP-Kp strains isolated from inpatients spread in the ICU of the hospital. Functionally, genes associated with information storage and processing of the ST11 XDR CP-Kp strains were more abundant than those of MDR and susceptible strains, especially genes correlative with mobile genetic elements (MGEs) such as transposons and prophages. Structurally, eleven large-scale genetic regions taken for the unique genome in these ST11 XDR CP-Kp strains were identified as MGEs including transposons, integrons, prophages, genomic islands, and integrative and conjugative elements. Three of them were located on plasmids and eight on chromosomes; five of them were with antimicrobial resistance genes and eight with adaptation associated genes. Notably, a new blaKPC-2-bearing ΔΔTn1721-blaKPC-2 transposon, probably transposed and truncated from ΔTn1721-blaKPC-2 by IS903D and ISKpn8, was identified in all six ST11 XDR CP-Kp strains. Conclusion Our findings suggested that together with clonal spread, MGEs identified uniquely in the ST11 XDR CP-Kp strains might contribute to their formidable adaptability, which facilitated their widespread dissemination in hospital.
Collapse
|
5
|
LytR-CpsA-Psr Glycopolymer Transferases: Essential Bricks in Gram-Positive Bacterial Cell Wall Assembly. Int J Mol Sci 2021; 22:ijms22020908. [PMID: 33477538 PMCID: PMC7831098 DOI: 10.3390/ijms22020908] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/14/2021] [Accepted: 01/14/2021] [Indexed: 12/28/2022] Open
Abstract
The cell walls of Gram-positive bacteria contain a variety of glycopolymers (CWGPs), a significant proportion of which are covalently linked to the peptidoglycan (PGN) scaffolding structure. Prominent CWGPs include wall teichoic acids of Staphylococcus aureus, streptococcal capsules, mycobacterial arabinogalactan, and rhamnose-containing polysaccharides of lactic acid bacteria. CWGPs serve important roles in bacterial cellular functions, morphology, and virulence. Despite evident differences in composition, structure and underlaying biosynthesis pathways, the final ligation step of CWGPs to the PGN backbone involves a conserved class of enzymes-the LytR-CpsA-Psr (LCP) transferases. Typically, the enzymes are present in multiple copies displaying partly functional redundancy and/or preference for a distinct CWGP type. LCP enzymes require a lipid-phosphate-linked glycan precursor substrate and catalyse, with a certain degree of promiscuity, CWGP transfer to PGN of different maturation stages, according to in vitro evidence. The prototype attachment mode is that to the C6-OH of N-acetylmuramic acid residues via installation of a phosphodiester bond. In some cases, attachment proceeds to N-acetylglucosamine residues of PGN-in the case of the Streptococcus agalactiae capsule, even without involvement of a phosphate bond. A novel aspect of LCP enzymes concerns a predicted role in protein glycosylation in Actinomyces oris. Available crystal structures provide further insight into the catalytic mechanism of this biologically important class of enzymes, which are gaining attention as new targets for antibacterial drug discovery to counteract the emergence of multidrug resistant bacteria.
Collapse
|
6
|
Augenstreich J, Briken V. Host Cell Targets of Released Lipid and Secreted Protein Effectors of Mycobacterium tuberculosis. Front Cell Infect Microbiol 2020; 10:595029. [PMID: 33194845 PMCID: PMC7644814 DOI: 10.3389/fcimb.2020.595029] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 09/22/2020] [Indexed: 12/12/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) is a very successful pathogen, strictly adapted to humans and the cause of tuberculosis. Its success is associated with its ability to inhibit host cell intrinsic immune responses by using an arsenal of virulence factors of different nature. It has evolved to synthesize a series of complex lipids which form an outer membrane and may also be released to enter host cell membranes. In addition, secreted protein effectors of Mtb are entering the host cell cytosol to interact with host cell proteins. We briefly discuss the current model, involving the ESX-1 type seven secretion system and the Mtb lipid phthiocerol dimycoserosate (PDIM), of how Mtb creates pores in the phagosomal membrane to allow Mtb proteins to access to the host cell cytosol. We provide an exhaustive list of Mtb secreted proteins that have effector functions. They modify (mostly inhibit but sometimes activate) host cell pathways such as: phagosome maturation, cell death, cytokine response, xenophagy, reactive oxygen species (ROS) response via NADPH oxidase 2 (NOX2), nitric oxide (NO) response via NO Synthase 2 (NOS2) and antigen presentation via MHC class I and class II molecules. We discuss the host cell targets for each lipid and protein effector and the importance of the Mtb effector for virulence of the bacterium.
Collapse
Affiliation(s)
| | - Volker Briken
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, United States
| |
Collapse
|
7
|
Li FKK, Rosell FI, Gale RT, Simorre JP, Brown ED, Strynadka NCJ. Crystallographic analysis of Staphylococcus aureus LcpA, the primary wall teichoic acid ligase. J Biol Chem 2020; 295:2629-2639. [PMID: 31969390 DOI: 10.1074/jbc.ra119.011469] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 01/20/2020] [Indexed: 12/12/2022] Open
Abstract
Gram-positive bacteria, including major clinical pathogens such as Staphylococcus aureus, are becoming increasingly drug-resistant. Their cell walls are composed of a thick layer of peptidoglycan (PG) modified by the attachment of wall teichoic acid (WTA), an anionic glycopolymer that is linked to pathogenicity and regulation of cell division and PG synthesis. The transfer of WTA from lipid carriers to PG, catalyzed by the LytR-CpsA-Psr (LCP) enzyme family, offers a unique extracellular target for the development of new anti-infective agents. Inhibitors of LCP enzymes have the potential to manage a wide range of bacterial infections because the target enzymes are implicated in the assembly of many other bacterial cell wall polymers, including capsular polysaccharide of streptococcal species and arabinogalactan of mycobacterial species. In this study, we present the first crystal structure of S. aureus LcpA with bound substrate at 1.9 Å resolution and those of Bacillus subtilis LCP enzymes, TagT, TagU, and TagV, in the apo form at 1.6-2.8 Å resolution. The structures of these WTA transferases provide new insight into the binding of lipid-linked WTA and enable assignment of the catalytic roles of conserved active-site residues. Furthermore, we identified potential subsites for binding the saccharide core of PG using computational docking experiments, and multiangle light-scattering experiments disclosed novel oligomeric states of the LCP enzymes. The crystal structures and modeled substrate-bound complexes of the LCP enzymes reported here provide insights into key features linked to substrate binding and catalysis and may aid the structure-guided design of specific LCP inhibitors.
Collapse
Affiliation(s)
- Franco K K Li
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada; Centre for Blood Research, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Federico I Rosell
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada; Centre for Blood Research, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Robert T Gale
- Department of Biochemistry and Biomedical Sciences, Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Jean-Pierre Simorre
- Université Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale, 38000 Grenoble, France
| | - Eric D Brown
- Department of Biochemistry and Biomedical Sciences, Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Natalie C J Strynadka
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada; Centre for Blood Research, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
| |
Collapse
|
8
|
Ballister ER, Samanovic MI, Darwin KH. Mycobacterium tuberculosis Rv2700 Contributes to Cell Envelope Integrity and Virulence. J Bacteriol 2019; 201:e00228-19. [PMID: 31285241 PMCID: PMC6755743 DOI: 10.1128/jb.00228-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 07/02/2019] [Indexed: 01/17/2023] Open
Abstract
The cell envelope of Mycobacterium tuberculosis is a key target for antibiotics, yet its assembly and maintenance remain incompletely understood. Here we report that Rv2700, a previously uncharacterized M. tuberculosis gene, contributes to envelope integrity. Specifically, an Rv2700 mutant strain had a decreased growth rate, increased sensitivity to antibiotics that target peptidoglycan crosslinking, and increased cell envelope permeability. We propose that Rv2700 be named a "cell envelope integrity" gene (cei). Importantly, a cei mutant had attenuated virulence in mice. Cei shares predicted structural homology with another M. tuberculosis protein, VirR (Rv0431), and we found that a virR mutant had growth rate, antibiotic sensitivity, and envelope permeability phenotypes similar to those of the cei mutant. Both Cei and VirR are predicted to consist of a transmembrane helix and an extracellular LytR_C domain. LytR_C domains have no known function, but they are also found in a family of proteins, the LytR-Cps2A-Psr (LCP) enzymes, that perform important cell envelope functions in a range of bacteria. In mycobacteria, LCP enzymes attach arabinogalactan to peptidoglycan, and mycobacterial LCP enzyme mutants have phenotypes similar to those of virR- and cei-deficient strains. Collectively, our results suggest that LytR_C domain proteins may contribute to the cell envelope functions performed by LCP proteins. This study provides a framework for further mechanistic investigations of LytR_C proteins and, more broadly, for advancing our understanding of the cell envelopes of mycobacteria and other medically and economically important genera.IMPORTANCEMycobacterium tuberculosis causes about 1.5 million deaths per year. The unique composition of the Mycobacterium tuberculosis cell envelope is required for this bacterium to cause disease and is the target for several critical antibiotics. By better understanding the mechanisms by which mycobacteria assemble and maintain their cell envelope, we might uncover new therapeutic targets. In this work, we show that a previously uncharacterized protein, Rv2700, is important for cell envelope integrity in Mycobacterium tuberculosis and that loss of Rv2700 attenuates virulence in mice. This family of proteins is found in a broad group of bacterial species, so our work provides a first insight into their potential functions in many species important to the environment, industry, and human health.
Collapse
Affiliation(s)
- Edward R Ballister
- Department of Microbiology, New York University School of Medicine, New York, New York, USA
| | - Marie I Samanovic
- Department of Microbiology, New York University School of Medicine, New York, New York, USA
| | - K Heran Darwin
- Department of Microbiology, New York University School of Medicine, New York, New York, USA
| |
Collapse
|
9
|
Sarmiento ME, Alvarez N, Chin KL, Bigi F, Tirado Y, García MA, Anis FZ, Norazmi MN, Acosta A. Tuberculosis vaccine candidates based on mycobacterial cell envelope components. Tuberculosis (Edinb) 2019; 115:26-41. [PMID: 30948174 DOI: 10.1016/j.tube.2019.01.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 01/12/2019] [Accepted: 01/16/2019] [Indexed: 12/11/2022]
Abstract
Even after decades searching for a new and more effective vaccine against tuberculosis, the scientific community is still pursuing this goal due to the complexity of its causative agent, Mycobacterium tuberculosis (Mtb). Mtb is a microorganism with a robust variety of survival mechanisms that allow it to remain in the host for years. The structure and nature of the Mtb envelope play a leading role in its resistance and survival. Mtb has a perfect machinery that allows it to modulate the immune response in its favor and to adapt to the host's environmental conditions in order to remain alive until the moment to reactivate its normal growing state. Mtb cell envelope protein, carbohydrate and lipid components have been the subject of interest for developing new vaccines because most of them are responsible for the pathogenicity and virulence of the bacteria. Many indirect evidences, mainly derived from the use of monoclonal antibodies, support the potential protective role of Mtb envelope components. Subunit and DNA vaccines, lipid extracts, liposomes and membrane vesicle formulations are some examples of technologies used, with encouraging results, to evaluate the potential of these antigens in the protective response against Mtb.
Collapse
Affiliation(s)
- M E Sarmiento
- School of Health Sciences (PPSK), Universiti Sains Malaysia (USM), 16150 Kubang Kerian, Kelantan, Malaysia
| | - N Alvarez
- Rutgers New Jersey Medical School, Public Health Research Institute, Newark, NJ, USA
| | - K L Chin
- Department of Biomedical Sciences and Therapeutic, Faculty of Medicine and Health Sciences (FPSK), Universiti Malaysia Sabah (UMS), Sabah, Malaysia
| | - F Bigi
- Institute of Biotechnology, INTA, Buenos Aires, Argentina
| | - Y Tirado
- Finlay Institute of Vaccines, La Habana, Cuba
| | - M A García
- Finlay Institute of Vaccines, La Habana, Cuba
| | - F Z Anis
- School of Health Sciences (PPSK), Universiti Sains Malaysia (USM), 16150 Kubang Kerian, Kelantan, Malaysia
| | - M N Norazmi
- School of Health Sciences (PPSK), Universiti Sains Malaysia (USM), 16150 Kubang Kerian, Kelantan, Malaysia.
| | - A Acosta
- School of Health Sciences (PPSK), Universiti Sains Malaysia (USM), 16150 Kubang Kerian, Kelantan, Malaysia.
| |
Collapse
|